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Cargo is tied with rope on the roof of a 45-foot tall car. The car travels down a road at 40 mi/h and hits a concrete barrier and the rope snaps, allowing the cargo to propel forward. Find the time it

takes for the cargo to hit the groupd and the horizontal distance the cargo travels. Let y represent height in feet, let x represent horizontal distance in feet, and let rrepresent time in seconds.
Equation 1:7-1611²+ 45
Equation 27-0047x²+45

1 Answer

4 votes

Answer:5.29 seconds to hit ground 30.86 feet in air

Explanation:

The first equation, y = 7.16t^2 - 40t + 45, represents the vertical position of the cargo as a function of time.

The second equation, y = -0.047x^2 + 45, represents the height of the cargo as a function of horizontal distance traveled.

To find the time it takes for the cargo to hit the ground, we need to find when y = 0 in the first equation.

Setting y = 0, we have:

0 = 7.16t^2 - 40t + 45

Solving for t, we can use the quadratic formula:

t = (-b ± √(b^2 - 4ac)) / (2a)

where a = 7.16, b = -40, and c = 45.

t = (40 ± √(40^2 - 4 * 7.16 * 45)) / (2 * 7.16)

t = (40 ± √(1600 - 322.2)) / (2 * 7.16)

t = (40 ± √1277.8) / (2 * 7.16)

t = (40 ± 35.62) / 14.32

t = (75.62 / 14.32, 4.38 / 14.32)

Since t must be positive, t = (75.62 / 14.32) = 5.29 s

Now that we have the time it takes for the cargo to hit the ground, we can use that time in the second equation to find the horizontal distance the cargo traveled.

x = √((45 - 0) / -0.047)

x = √(45 / -0.047)

x = √(45 * -21.28) = √(957) = 30.86 ft

So, it takes the cargo 5.29 seconds to hit the ground, and it travels 30.86 feet horizontally.

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